Need Investing Assistance from Experienced Investor?

Here's my situation. I currently have 401K with my job. I work for the Government so its called Thrift Savings Plan. I contribute 5% of my earnings each pay period and they match 5% each pay period. My wife job automatically takes 3% out each pay period whether she matches or not. We are looking at investing options. To increase her retirement contribution, she wants to invest in an Roth IRA and have ETF under it for example to have a target date fund so she could start out aggressive investing and then as the years go by be less aggressive. I'm 29 and she's 28. I wanted to also have another investing vessel for us. I was thinking of a mutual fund and systematically funding that every month. My question, if we open a Roth IRA and a ETF under the roth for her retirement, what other possible investing options we could use outside of saving for our retirement? As I mentioned I was thinking of a mutual fund - I'm open to hear some possible avenues we can seek. Thanks